Conduit Bending
Saddle bends, offsets, kicks, segment bends, rolling offsets, and conduit bend multipliers for field layout.
Electrical Calculators for Motors, Solar, Voltage Drop, and Loads
Find calculators for motors, conduit bends, wire sizing, voltage drop, lighting, solar, backup power, and test readings.
Calculator Categories
Browse calculation families by equipment, field task, and electrical method.
Electrical Formulas
Voltage, current, resistance, power, energy, power factor, and cost calculators for basic electrical math.
Estimating And Material Planning
Material takeoff, conduit cut length, wire pull length, waste allowance, and job quantity calculators.
Lighting And Illumination
Lumens, footcandles, lux, fixture count, lighting load, emergency lighting, and lighting energy calculators.
Load Calculations
Residential, commercial, industrial, feeder, panel, service, appliance, HVAC, and EV load calculators.
Motors And Power Quality
Motor current, starter sizing, VFD checks, transformer kVA, generator load, harmonics, and power quality.
Solar And Backup Power
Battery capacity, runtime, inverter size, UPS capacity, generator load, fuel use, and backup power planning.
Solar And PV Systems
PV array size, solar panel count, string voltage, cable voltage drop, charge controller checks, and solar energy output.
Testing, Protection And Grounding
Insulation resistance, short-circuit current, pull-box sizing, grounding, bonding, touch voltage, and protection checks.
Wire, Cable And Raceway
Wire size, cable resistance, raceway fill, ampacity, voltage drop, bend radius, and pull-length calculators.
Available Calculators
Open a calculator to enter values, inspect the formula, and read the result units.
Wire Pull Length Calculator
Record measured route segments and bend allowances to estimate total pull length before a wire-pull review.
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Watts Volts Amps Calculator (Real Power to Current)
Calculate current and apparent power from real power, voltage, phase model, and power factor.
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Voltage Presence Check Calculator
Document an absolute voltage-reading comparison against an entered display threshold and nominal-voltage reference without replacing approved absence-of-voltage procedures.
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Voltage From Power And Current Calculator
Calculate ideal voltage from entered real power in watts and current in amperes using direct algebra.
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Voltage Drop Across Resistor Calculator (I x R and Power)
Calculate resistor voltage drop and power dissipation from current and resistance.
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Voltage Drop Length Calculator
Solve the inverse voltage-drop relationship for maximum one-way length while keeping conductor selection and installation review outside the formula.
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VFD Harmonic Current Calculator
Calculate per-drive and fleet harmonic RMS current from fundamental current, current THD, drive count, and an entered comparison reference.
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UPS Runtime Calculator (Battery Backup Hours)
Calculate UPS runtime and battery backup duration from usable battery energy, load power, conversion efficiency, and reserved energy before checking the manufacturer runtime curve.
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UPS Battery Size Calculator (Ah, Wh, kWh)
Provide a preliminary UPS battery energy and amp-hour estimate from load power, target runtime, conversion efficiency, usable capacity, and battery voltage.
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Transformer UPS Capacity Calculator
Provides a preliminary comparison of UPS apparent load and reserve-adjusted transformer demand against an entered transformer capacity.
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Transformer Short Circuit Contribution Calculator
Provides a preliminary transformer-limited fault-current estimate from transformer kVA, secondary voltage, phase model, and percent impedance.
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Transformer Service Factor Calculator
Provides a preliminary comparison of entered load kVA with a service-factor-adjusted transformer capacity when the factor is documented for the exact equipment and duty.
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Transformer Secondary Current Calculator
Provides a preliminary transformer secondary line-current estimate from rated kVA, secondary voltage, and a single-phase or balanced three-phase model.
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Transformer Primary Current Calculator
Provides a preliminary transformer primary line-current estimate from rated kVA, primary voltage, and a single-phase or balanced three-phase model.
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Transformer Percent Impedance Test Calculator
Provides a transformer percent-impedance estimate from test voltage on the rated winding after confirming that test current matches the rated-current basis.
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Transformer Inrush Duration Calculator
Calculate the cycles and seconds for a simplified transformer inrush current to decay from an initial multiplier to an entered target multiplier.
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Transformer Harmonic Heating Calculator
Calculate total RMS current and a THD-weighted transformer stray-loss factor from fundamental current, current THD, base stray loss, and an entered weighting multiplier.
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Transformer Grounding Resistor Calculator
Calculate neutral-grounding-resistor resistance, fault power, fault energy, and current-rating margin from entered voltage, fault current, and clearing duration.
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Transformer Generator Coordination Calculator
Compare transformer load with entered generator kVA and kW ratings, showing capacity margins and the limiting utilization.
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Transformer Delta-Wye Voltage Calculator
Calculate ideal secondary line-to-line and line-to-neutral voltage from primary line voltage, turns ratio, and the selected delta or wye connection.
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Transformer Cooling Load Calculator
Convert transformer losses and operating assumptions into adjusted heat load, BTU per hour, cooling tons, and daily heat energy for HVAC coordination.
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Transformer Bank Capacity Calculator
Calculate combined transformer-bank nameplate capacity, usable capacity, and reserved capacity for identical units under an entered utilization assumption.
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Touch Voltage Safety Screen Calculator
Calculate touch voltage from fault current, grid resistance, and touch fraction, then compare it with an entered review value.
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Time-of-Use Electricity Cost Calculator (Peak, Shoulder, Off-Peak)
Calculate time-of-use electricity cost from peak, shoulder, and off-peak kWh, each period rate, and a fixed charge.
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